Q27 of 40 Page 1

Find the zeroes of the quadratic polynomial x2 – 3x – 10 and verify the relationship between the zeroes and coefficient.

⇒ x2 – 3x – 10 = 0


⇒ x2 – 5x + 2x – 10 = 0


⇒ x(x - 5) + 2(x – 5) = 0


⇒ (x + 2) × (x – 5) = 0


⇒ x = -2, 5


Let α = -2 and β = 5


So the relationship between zeroes and coefficient are:



Taking 1st equation,


LHS = α + β = 3


RHS


So, LHS = RHS


Taking 2nd equation,


LHS = α β = -10


RHS


So, LHS = RHS


Hence, the relationship is verified.


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